Rocker Studs

This is the new exh. studs for the TFS A460 heads......1.300" under head.

what is the max rpm for the for that hardware setup ? stud/girdle ........

Phillip has turned his A460 T/D deal 8,000 RPM...he does not have the new style studs.

bruno wrote:what is the max rpm for the for that hardware setup ? stud/girdle ........

That depends on several factors, including the weight of the valves, the valve springs seat and open pressure, the camshaft's rate of opening and closing, rocker arm ratio, valvetrain harmonics and etc.

The nice thing about what Lem has pictured, is that you get more threads of engagement between your rocker stud and the alum. head. Many of the rocker studs in use now on lesser heads, where designed back in the old days, when guys were screwing them into cast iron heads. Maybe that's not enough threads of engagement into alum. heads. For example, the head studs for an alum. aftermarket block, have twice the length of coarse threads on them, as compared to the head studs for an iron block.

Hope this helps,
Charlie

I have studs like that (1.300) and the other set are shorter...am I to assume that the short threaded studs are the intakes?...they came with the new (received in april 2011) 18 bolt TFS A's with the square stud boss pad...

1.300" are the exh.

then I'm up to date and all set....thanks

Lem Evans wrote:This is the new exh. studs for the TFS A460 heads......1.300" under head.

That's somewhere between the saucerhead and the foreskin, isn't it? ... ...

LivermoreDave wrote:

Lem Evans wrote:This is the new exh. studs for the TFS A460 heads......1.300" under head.

That's somewhere between the saucerhead and the foreskin, isn't it? ... ...

i havent figured you out yet Mr. Livermore

All B.S. aside, and it's not always possible, I like as much threads in the cylinder head as possible. I don't think it beneficial to the stud so much as to the head stud boss. The stud is going to bend from the cylinder head stud boss seat, up. And bend it will! With the pissy springs I use, I've found the studs will bend and it seem to effect the relation of the rocker tip's contact with the valve tip. We generally tend to replace the studs during rebuilds and sometimes before if they start leaning to far!

Just my invaluable $0.02.
Dave.

A lot of years ago, studs of that nature from Manley were used on the exhaust side of some Chevrolet factory aluminum heads to keep from pulling the raised stud boss off the head casting when the RPM and spring pressures were being raised for higher horsepower.

Quite a few people who didn't really know cylinder heads were buying them and using them but, couldn't understand why it wasn't curing their problem. Those heads had heli-coils in the stud bosses and if you didn't put new longer coils in the them, no matter how long the stud got the heli-coil still only went so deep.
Fixed a lot of 'em before aftermarket aluminum heads became popular.